Glass bottles, are used as containers for beer, fruit juice, and so forth. Usually, after being used, they are recovered for reuse.
When bottles are recovered and used repeatedly, an abrasion is formed in the external surface, particularly the shoulder portion thereof at the time of bottling or in the course of transportation. This will deteriorate their appearance and reduce their goods value.
Hence, when such abrasions are formed in recovered bottles, it is necessary to cover the abrasive portion of the bottle by any suitable means. One means is to apply a coating material onto the abrasive portion of the bottle.
Various coating materials have heretofore been proposed to cover an abrasion of a bottle. Although conventional coating materials are superior in the effect of covering an abrasion, they have some disadvantages. One of the disadvantage is that the coating material has poor drying properties because of its high hygroscopicity, and thus it becomes sticky and is liable to catch dust. Another disadvantage is that since the coating material adheres strongly to the bottles, it cannot be completely removed even after passing the bottles through the bottle-washing step. Furthermore, some of the coating materials as heretofore proposed are not suitable for practical use of their high price, or are not desirable from a hygienic standpoint or from a viewpoint of safety.
Hence it is required for a coating material to be applied onto an abrasive portion of bottle to meet the following requirements: (1) the effect of covering an abrasive portion is good, (2) emulsion stability is good and coating workability is superior, (3) drying properties are good, and it does not become sticky, (4) water resistance is superior, (5) it can be completely removed at the bottle-washing step, (6) it is not harmful from a viewpoint of food sanitation, and (7) it is inexpensive and is available stably.
The present invention is intended to provide a coating material satisfying all the requirements as described above.